Cessna 441 pilot has loss of pressurization; descends and regains control of cabin pressure.

Attributes
ACN	726822
Time
Date	200702
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : vxv.vortac
State Reference	GA
Altitude	msl single value : 26000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ztl.artcc
Operator	general aviation : corporate
Make Model Name	Conquest I/Conquest II
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial pilot : cfi pilot : multi engine pilot : atp
Experience	flight time last 90 days : 155 flight time total : 10000 flight time type : 600
ASRS Report	726822
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : cabin alt warning other flight crewa
Resolutory Action	controller : provided flight assist
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Flight Crew Human Performance

Narrative:

While cruising at 26000 ft I became ill (or so I thought). In fact; the aircraft was not maintaining cabin pressure. I was flying southwest into a very bright sun. I put on dark sunglasses for eye comfort. The cabin altitude light was on but I could not see it. I keep a small first aid kit behind the seat; when I turned to get it I saw the oxygen mask in the cabin had deployed. After some confusion; I put on my oxygen mask and asked for lower. The controllers did a great job when I told him I needed to get down. After my head cleared up some I leveled off and discover I had pulled the cabin dump valve with my pant leg. I know it sounds impossible but it happened!

Original NASA ASRS Text

Title: CESSNA 441 PLT HAS LOSS OF PRESSURIZATION; DSNDS AND REGAINS CTL OF CABIN PRESSURE.

Narrative: WHILE CRUISING AT 26000 FT I BECAME ILL (OR SO I THOUGHT). IN FACT; THE ACFT WAS NOT MAINTAINING CABIN PRESSURE. I WAS FLYING SW INTO A VERY BRIGHT SUN. I PUT ON DARK SUNGLASSES FOR EYE COMFORT. THE CABIN ALT LIGHT WAS ON BUT I COULD NOT SEE IT. I KEEP A SMALL FIRST AID KIT BEHIND THE SEAT; WHEN I TURNED TO GET IT I SAW THE OXYGEN MASK IN THE CABIN HAD DEPLOYED. AFTER SOME CONFUSION; I PUT ON MY OXYGEN MASK AND ASKED FOR LOWER. THE CTLRS DID A GREAT JOB WHEN I TOLD HIM I NEEDED TO GET DOWN. AFTER MY HEAD CLRED UP SOME I LEVELED OFF AND DISCOVER I HAD PULLED THE CABIN DUMP VALVE WITH MY PANT LEG. I KNOW IT SOUNDS IMPOSSIBLE BUT IT HAPPENED!

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.